<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>班级名单</title>
    <style type="text/css">
        #ikun{
            margin: 0px auto;
            height: 500px;
            width: 500px;
        }
        td{
            border: solid 1px red;
            text-align: center;
            width: auto;
            height: auto;
            font-weight: bold;
        }
    </style>
    <script>
        function fn(){
            var num = parseInt(Math.random() * 41 + 1);
            var tdObj = document.getElementById('td' + num);
            tdObj.style.backgroundColor = 'red';
            document.getElementById('sp').innerText = '答题人是:' + tdObj.innerText;
        }
        function begin(){
            for (let i = 1; i <= 42; i++) {
                var tdObj = document.getElementById('td' + i);
                tdObj.style.backgroundColor = 'white';
            }
            document.getElementById('sp').innerText = '正在抽人中...'
            setTimeout(fn, 3000);
        }
    
    </script>
</head>
<body>
     <!-- setInterval: 班级回答问题 -->
     <div id="btn" style="text-align: center; margin:50px">
        <button onclick="begin()">点击抽人</button>
        <span id="sp"></span>
    </div>
     <table id="ikun">
        <tr>
            <td id="td1">郑玮喆</td>
            <td id="td2">庄云</td>
            <td id="td3">廖治先</td>
            <td id="td4">郑文源</td>
            <td id="td5">戴俊锋</td>
        </tr>
        <tr>
            <td id="td6">陈昊童</td>
            <td id="td7">谢金金</td>
            <td id="td8">占志新</td>
            <td id="td9">张淑芳</td>
            <td id="td10">刘永潘</td>
        </tr>
        <tr>
            <td id="td11">廖柏成</td>
            <td id="td12">郑宗帅</td>
            <td id="td13">李韦峰</td>
            <td id="td14">吴欣燕</td>
            <td id="td15">陈梅香</td>
        </tr>
        <tr>
            <td id="td16">陈立智</td>
            <td id="td17">袁贵森</td>
            <td id="td18">赵浩敏</td>
            <td id="td19">林世涛</td>
            <td id="td20">罗启恒</td>
        </tr>
        <tr>
            <td id="td21">卢国建</td>
            <td id="td22">黄柱菘</td>
            <td id="td23">陈鹏</td>
            <td id="td24">张耀仁</td>
            <td id="td25">陈华伟</td>
        </tr>
        <tr>
            <td id="td26">张正豪</td>
            <td id="td27">韦仲晓</td>
            <td id="td28">黄富贵</td>
            <td id="td29">陆建锋</td>
            <td id="td30">曾德森</td>
        </tr>
        <tr>
            <td id="td31">吴文龙</td>
            <td id="td32">陆利群</td>
            <td id="td33">黄雄</td>
            <td id="td34">王世财</td>
            <td id="td35">张先杰</td>
        </tr>
        <tr>
            <td id="td36">胡基耀</td>
            <td id="td37">马鑫涛</td>
            <td id="td38">李涛</td>
            <td id="td39">杨凌翔</td>
            <td id="td40">罗此东</td>
        </tr>
        <tr>
            <td id="td41">唐皓颖</td>
            <td id="td42">白婉婷</td>
            <td id="td43">下课</td>
            <td id="td44">放学</td>
            <td id="td45">放假</td>
        </tr>
     </table>
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</body>
</html>